CN111378469B

CN111378469B - Residual oil hydrodemetallization method

Info

Publication number: CN111378469B
Application number: CN201811605760.XA
Authority: CN
Inventors: 李洪广; 耿新国; 刘铁斌; 翁延博; 金建辉; 蒋立敬; 袁胜华
Original assignee: China Petroleum and Chemical Corp; Sinopec Dalian Research Institute of Petroleum and Petrochemicals
Current assignee: Sinopec Dalian Petrochemical Research Institute Co ltd; China Petroleum and Chemical Corp
Priority date: 2018-12-27
Filing date: 2018-12-27
Publication date: 2021-07-09
Anticipated expiration: 2038-12-27
Also published as: CN111378469A

Abstract

The invention discloses a residual oil hydrodemetallization method. In the method, a feed comprises a residual oil raw material, hydrogen and a material viscosity adjusting aid, wherein the material viscosity adjusting aid comprises ethylene tar, and the feed is subjected to a hydrotreating reaction in a hydrodemetallization reaction zone to obtain a hydrogenation effluent; the hydrodemetallization reaction zone is filled with at least one hydrodemetallization catalyst and at least one hydrogenation protective agent. The method adopts ethylene tar as a material viscosity regulating auxiliary agent to be added into the residual oil raw material, can effectively reduce the system viscosity under the reaction condition through the synergistic action of all components under the condition of the hydrodemetallization reaction, promotes the residual oil hydrodemetallization, and is also beneficial to the improvement of the subsequent reactivity of desulfurization, residual carbon removal and the like.

Description

Residual oil hydrodemetallization method

Technical Field

The invention relates to a hydrocarbon hydrotreating technology, in particular to a residual oil hydrodemetallization method.

Background

The residual oil hydrogenating technology is that under the conditions of high temperature, high pressure and catalyst, residual oil and hydrogen gas are catalytically reacted to eliminate sulfur, nitrogen, metal and other harmful impurities from residual oil molecule, and partial great molecule in residual oil is cracked and hydrogenated to become ideal component with small molecule.

Compared with other residual oil processing technologies, the fixed bed hydrotreating technology has low investment and operation cost and safe and simple operation, and is the residual oil processing technology which has the most industrial application and the most mature technology so far. The fixed bed residual oil hydrogenation device can provide qualified feed for a catalytic cracking device, and simultaneously generate part of light products such as gasoline, diesel oil and the like.

The residual oil raw material has high density and high viscosity, so that the residual oil raw material is not beneficial to the diffusion of the residual oil raw material in a pore channel of a residual oil hydrotreating catalyst, and particularly, macromolecular substances such as colloid, asphaltene and the like in the raw material cannot enter a micropore of the catalyst and cannot be converted into micromolecular substances through reaction, so that the impurity removal rate and the residual carbon removal rate in the residual oil hydrotreating reaction are influenced, and the service life and the operation stability of the catalyst are also influenced. The greater the feed viscosity, the greater the system pressure drop and flow fluctuation, and the poorer the operating stability. Moreover, because of high metal content and high carbon residue value in residual oil, asphaltene coagulation phenomenon can occur when the conversion rate is low, so that the catalyst is quickly inactivated due to carbon deposition, and the operation period of the device is shortened. At present, in order to control indexes such as proper raw material viscosity and the like, a raw material of a residual oil hydrogenation device is blended with light oil products (such as coker gas oil, catalytic cracking diesel oil, cycle oil, gas oil and the like) with low density, low viscosity and low carbon residue to adjust processing indexes such as raw material viscosity, carbon residue and the like, so as to meet the processing requirements of the device.

CN106367113A discloses a residual oil hydrotreating method. The method uses a residual oil fixed bed hydrogenation device, the residual oil raw material is doped with inferior light oil, the inferior light oil is sequentially subjected to hydrogenation protective agent, hydrodemetallization catalyst, hydrodesulfurization catalyst, hydrodenitrogenation catalyst and hydrodecarbonization catalyst, and the product is fractionated to obtain gasoline, kerosene, diesel oil fraction and hydrogenation tail oil. The poor light oil can be catalytic cracking diesel oil, medium oil, cracking diesel oil or carbon ten heavy aromatics. The method can reduce the viscosity of a feeding system of the residual oil fixed bed hydrogenation device and improve the reaction performance and the product quality of the system.

CN1488719A discloses a heavy hydrocarbon hydrotreating method, in which a residual oil raw material sequentially passes through a protective agent bed layer, a hydrodemetallization catalyst bed layer, a hydrodesulfurization catalyst bed layer and a hydrodenitrogenation catalyst bed layer, and deasphalted oil and/or coker wax oil is introduced behind the protective agent bed layer and before the hydrodesulfurization catalyst bed layer, and the introduction position of the deasphalted oil and/or coker wax oil is behind part of the hydrodemetallization catalyst bed layer. The method is used for the common hydrotreatment of residual oil, deasphalted oil and coker gas oil, and provides high-quality feed for downstream catalytic cracking or hydrocracking and other light devices.

Ethylene tar is a byproduct in ethylene production, accounting for about 15% of ethylene yield, and is composed of various alkanes and C₈～C₁₅Mainly is a mixture of aromatic hydrocarbons with more than two rings and condensed rings, the aromatic hydrocarbon content is more than 90%, and the density (20 ℃) is 1.0g/cm³Above, the content of impurities such as sulfur, nitrogen and the like is low, metal impurities (containing trace metal impurities such as iron and the like which are mainly brought in due to equipment corrosion) are basically not contained, the viscosity (100 ℃) reaches more than 200 mm/s, which is far higher than that of the conventional residual oil hydrotreating raw material, and the raw material is not suitable for reducing viscosity components for residual oil hydrogenation, and meanwhile, the raw material does not contain metal impurities basically and does not need hydrogenation demetallization reaction generally. The fraction of ethylene tar before 350 ℃ accounts for about 30-40 percent and is light oil; the fraction after 350 ℃ is heavy oil and black solid at normal temperature, and accounts for about 60-70%. In recent years, with the rapid development of the ethylene industry, the yield of ethylene tar is also rapidly increased, so that the ethylene tar is reasonably utilized to generate higher economic benefit, which has great influence on the overall benefit of an ethylene device and the deep processing of ethylene byproduct resources, and is one of the important issues to be solved in the ethylene post-processing industry at present.

The research on the comprehensive utilization of ethylene tar mainly comprises the following aspects: (1) extracting naphthalene, methylnaphthalene and series thereof from ethylene tar; (2) preparing carbon petroleum resin, fiber asphalt, carbon fiber and the like by using the ethylene tar; (3) blending light fraction of the ethylene tar into other devices for further processing; (4) the ethylene tar is prepared into aromatic solvent oil, needle coke and carbon black.

Because of the complexity of the components of the ethylene tar, the research is not applied to large scale in industry, at present, the ethylene tar is mainly used as fuel oil of a boiler or a kiln, only a small part of the ethylene tar is processed to produce carbon black, the overall utilization rate is not high, the economic value is low, and the ethylene tar contains heavy alkenyl aromatic hydrocarbon and the like, so that black smoke and coking are easily generated during combustion to cause environmental pollution, and the processing technology for the ethylene tar has the defects of harsh technological conditions, high cost, low conversion rate of the ethylene tar, low product yield, low comprehensive utilization rate, low product added value and the like.

CN1970688A discloses a comprehensive processing technique of ethylene tar. The process comprises the steps of cutting light fractions with the boiling point of less than 260-280 ℃ from ethylene tar, removing unsaturated hydrocarbons in the light fractions by a hydrofining method, then extracting naphthalene and methylnaphthalene products from the light fractions, and simultaneously obtaining a small amount of solvent naphtha products as byproducts. The method only utilizes the light fraction which accounts for a small proportion of the ethylene tar, and the ethylene tar fraction of more than about 80 percent is not effectively treated; meanwhile, the provided hydrofining conditions can not treat the ethylene tar fraction with the boiling point higher than 280 ℃.

CN102234538A discloses a method for hydrotreating ethylene tar. The method comprises the steps of fractionating ethylene tar into light fraction and heavy fraction, wherein the cutting point is 400-450 ℃, the light fraction sequentially passes through a hydrogenation protection catalyst, a hydrofining catalyst, a hydrogenation carbon residue removal catalyst and a hydrocracking catalyst, and the obtained products are separated to obtain gasoline fraction and diesel oil fraction; the heavy fraction passes through a hydrogenation protection catalyst, a hydrogenation carbon residue removal catalyst and a hydrogenation conversion catalyst in sequence, the obtained hydrogenation conversion generated oil is circularly removed from a heavy fraction hydrogenation reaction zone, and the rest part is separated to obtain gasoline and diesel oil fractions. The method for processing the ethylene tar independently has the advantages that the requirements on a hydrogenation device and matched equipment are increased due to the high density and high viscosity of the heavy fraction, a fractionating tower is additionally arranged for cutting the ethylene tar, a large amount of hydrogenation conversion generated oil circulation is needed for processing the heavy fraction, the technical process is complex, and industrialization is difficult to realize.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a residual oil hydrodemetallization method. The inventor of the invention unexpectedly finds that the ethylene tar is used as the material viscosity regulating auxiliary agent and added into the residual oil raw material, so that the system viscosity under the reaction condition can be effectively reduced under the condition of the hydrodemetallization reaction through the synergistic effect of all components, the residual oil hydrodemetallization is promoted, and the improvement of the subsequent reactivity of desulfurization, carbon residue removal and the like is facilitated.

For residue hydrogenation, the nature of the feedstock and the catalyst deactivation profile are two important factors affecting residue hydrogenation. The hydrogenation of the residual oil is a diffusion-controlled reaction, and the viscosity of the raw oil and the size of the reactant molecules have a great influence on the diffusion, so that the viscosity of the raw oil is generally reduced, the size of the reactant molecules is reduced, the diffusion performance of the raw oil is further improved, and the hydrogenation of the residual oil is promoted in the field. Particularly in the residual oil hydrodemetallization reaction zone, because the reaction temperature is relatively lower and the residual oil conversion rate is relatively lower (less components with low molecular weight and low viscosity are generated) than those in the subsequent hydrodesulfurization and hydroconversion reaction zones, the viscosity of the material in the stage is higher, and the influence of the viscosity on the reaction in the stage is more prominent. The catalyst can affect the pore structure and the surface performance of the catalyst due to metal deposition or carbon deposition and the like, and further affect the diffusion and the reaction performance of the catalyst. The ethylene tar has high content of polycyclic aromatic hydrocarbon and high viscosity, and if the ethylene tar is used as a residual oil hydrotreating raw material, the residual oil hydrogenation is not favorable from the aspects of raw material properties and catalyst deactivation. The inventors have surprisingly found that, although the ethylene tar does not meet the conventional requirements for improving the hydrogenation performance of the residual oil in terms of composition and properties, particularly on the hydrodemetallization reaction zone of the residual oil, but the inventor unexpectedly adds the ethylene tar as a material viscosity adjusting auxiliary agent to the residual oil raw material, under the condition of hydrogenation demetallization reaction, the demetallization performance of the reaction system is not reduced but promoted, the indexes such as viscosity, metal removal rate and the like of the reaction effluent in the stage are obviously improved, and the diffusion performance of the reaction system under the condition of the hydrodemetallization reaction can be judged to be more favorable for the demetallization reaction, the system viscosity under the reaction condition is effectively reduced under the synergistic effect of the components, the residual oil hydrodemetallization is promoted, and the improvement of the subsequent reactive performances such as desulfurization, carbon residue removal and the like is also favorable. The inventor further researches and discovers that the conventional hydrodemetallization reaction zone is generally filled with a hydrodemetallization catalyst, the filling principle of the hydrodemetallization catalyst is generally along the direction of liquid-phase material flow, the activity of the hydrodemetallization catalyst is gradually increased, the particle size of the hydrodemetallization catalyst is gradually reduced, the pore diameter of the hydrodemetallization catalyst is gradually reduced, and the like.

The residual oil hydrodemetallization method provided by the invention comprises the steps that the feed comprises a residual oil raw material, hydrogen and a material viscosity adjusting aid, wherein the material viscosity adjusting aid comprises ethylene tar, and the feed is subjected to a hydrotreating reaction in a hydrodemetallization reaction zone to obtain a hydrogenation effluent; the hydrodemetallization reaction zone is filled with at least one hydrodemetallization catalyst and at least one hydrogenation protective agent.

The invention provides a residual oil hydrodemetallization method.A hydrodemetallization reaction zone mainly carries out hydrodemetallization reaction, and simultaneously carries out reactions such as hydrodesulfurization, hydrodecarbonization and the like.

Furthermore, a hydrogenation protective agent is arranged in the middle of the hydrogenation demetallization catalyst.

Further, according to the direction of liquid phase material flow, the hydrogenation demetalization catalyst and the hydrogenation protective agent are alternately filled in the hydrogenation demetalization reaction zone, and preferably, the hydrogenation demetalization catalyst is arranged on the layer at the most upstream and the layer at the most downstream.

Further, when the hydrogenation demetallization catalyst and the hydrogenation protective agent are alternately filled, the hydrogenation protective agent is preferably filled for 1-4 times, and preferably for 1-3 times.

Further, the total filling volume of the hydrogenation protective agent accounts for 1-12% of the total volume of the catalyst in the hydrogenation demetallization reaction zone, and preferably 2-10%.

Further, when the hydrodemetallization catalyst and the hydrogenation protective agent are alternately filled, the hydrogenation protective agent in any layer accounts for 1-16% of the filling volume of the upstream adjacent layer of the hydrodemetallization catalyst, and preferably 2-14%. Furthermore, the filling volume of any layer of the hydrodemetallization catalyst accounts for 10-70% of the total volume of the hydrodemetallization reaction zone catalyst.

In the residual oil hydrodemetallization method, the same hydrogenation protective agent can be adopted as the hydrogenation protective agent, and different hydrogenation protective agents can also be adopted as the hydrogenation protective agent. Preferably, along the direction of liquid phase material flow, the grading principle activity of the hydrogenation protective agent increases layer by layer, and the pore diameter decreases layer by layer.

The dosage of the ethylene tar accounts for 0.1-30% of the mass of the residual oil raw material, preferably 5-20%, and further preferably 8-20%.

The properties of the ethylene tar are as follows: the density (20 ℃ C.) was 1.000g/cm³Above, it is generally 1.000 to 1.200g/cm³The carbon residue content is 10-30 wt%, the condensation point is 30-40 ℃, and the viscosity at 100 ℃ is 200-500 mm/s.

The ethylene tar is low in sulfur and nitrogen content and basically free of metal impurities, wherein the sulfur content is less than 0.05wt%, generally 0.03wt% to 0.05wt%, the nitrogen content is less than 80 mug/g, generally 10 to 80 mug/g, and the Ni and V content is less than 5 mug/g, and further less than 3 mug/g.

The residual oil raw material is a raw material commonly used by a residual oil hydrotreater, and can comprise atmospheric residual oil and/or vacuum residual oil. Optionally, the residual oil feedstock may further include conventional auxiliary materials for improving residual oil properties, facilitating processing, etc., such as adding a low-density, low-viscosity light oil for controlling proper feedstock viscosity, etc., wherein the light oil may be one from straight run, vacuum, or secondary processing, such as at least one of wax oil, diesel oil, gas oil, etc., and wherein the secondary processing may be at least one of coking, catalytic cracking, visbreaking, etc. For example, the wax oil may be one or more of straight-run wax oil, vacuum wax oil, and coker wax oil, and the light oil obtained by catalytic cracking may be at least one of catalytic cracking diesel oil, catalytic cracking cycle oil, and catalytic cracking cycle oil. The addition amount of the conventional auxiliary raw materials can be adjusted by those skilled in the art according to the properties of the raw materials and the like.

The properties of the resid feedstock are as follows: the density (20 ℃) is 0.955-0.996 g/cm³The carbon residue content is 9-14 wt%, the content of metal impurities is 10-110 mu g/g calculated by Ni and V, the condensation point is 27-38 ℃, and the viscosity at 100 ℃ is 60-120 mm/s.

The residual oil raw material has high sulfur and nitrogen contents, wherein the sulfur content is generally 0.8-3.5 wt%, and the nitrogen content is generally 1500-5000 mug/g.

In the residual oil hydrodemetallization method, the operation conditions of the hydrodemetallization reaction zone are as follows: the reaction temperature is 300-410 ℃, the hydrogen partial pressure is 10-20 MPa, and the liquid hourly space velocity is 0.1-2.0 h^-1The volume ratio of hydrogen to oil is 500-2000, and the preferable operation conditions are as follows: the reaction temperature is 350-395 ℃, the hydrogen partial pressure is 13-18 MPa, and the liquid hourly space velocity is 0.1-1.5 h^-1The volume ratio of hydrogen to oil is 500-2000.

In the residue hydrodemetallization method, a fixed bed hydrogenation process is preferably adopted, wherein the reactor containing the hydrodemetallization reaction zone can adopt an upflow feeding mode or a downflow feeding mode.

In the residual oil hydrodemetallization method, a hydrogenation protection reaction zone can be arranged, which can be determined by the skilled person according to the properties of the raw material. The hydrogenation protection reaction zone is arranged before the hydrogenation demetallization reaction zone. The hydrogenation protection reaction zone is at least filled with one hydrogenation protection agent bed layer, and preferably 2-4 hydrogenation protection agent bed layers.

In the residue hydrodemetallization method, the hydrogenation protective agent and the hydrodemetallization catalyst can be selected from conventional commercial catalysts in the field or prepared by adopting a conventional method in the prior art. The catalyst comprises a carrier and an active metal component, wherein the carrier can be an alumina-based carrier, and at least one of boron, silicon, zirconium, phosphorus, fluorine, titanium and the like can be added, the active metal component is generally selected from one or more of group VIB and/or group VIII metals, the group VIII metal is preferably Ni and/or Co, and the group VIB metal is preferably Mo and/or W. The catalyst of the present invention may be in the form of an extrudate or a sphere. For example, FZC series commercial catalysts developed by the institute of petrochemical and comforting petrochemical industries of china, such as hydrogenation protectors FZC-100B, FZC-12B, FZC-103D, FZC-13B, hydrodemetallization catalysts FZC-28A, FZC-204A, and the like, can be used.

In the residual oil hydrodemetallization method, the mass content of hydrogenation active metals in the hydrogenation protective agent is 3-12% in terms of oxides, wherein the mass content of VIB group metals in the hydrogenation protective agent is 2.0-11.5% in terms of oxides, and the mass content of VIII group metals in the hydrogenation protective agent is 0.2-5.0% in terms of oxides.

In the residual oil hydrodemetallization method, the mass content of the hydrogenation active metal in the hydrodemetallization catalyst is 4-22% in terms of oxide, wherein the mass content of the VIB group metal in terms of oxide is 3-21%, and the mass content of the VIII group metal in terms of oxide is 0.5-6.0%.

The viscosity of the hydrogenation effluent obtained by the residual oil hydrodemetallization method is smaller than that of the hydrogenation effluent obtained by independently taking a residual oil raw material as a liquid-phase feed and adopting no hydrogenation protective agent in a hydrodemetallization reaction zone. Wherein the viscosity means the viscosity at 100 ℃ in mm/s.

The removal rate of metal Ni and metal V in the hydrogenation effluent obtained by the residual oil hydrodemetallization method is higher than that of the hydrogenation effluent obtained by independently taking a residual oil raw material as a liquid-phase feed and adopting no hydrogenation protective agent in a hydrodemetallization reaction zone.

The removal rate of sulfur in the hydrogenation effluent obtained by the residual oil hydrodemetallization method is higher than that of the hydrogenation effluent obtained by independently taking a residual oil raw material as a liquid-phase feed and adopting no hydrogenation protective agent in a hydrodemetallization reaction zone.

The hydrogenation effluent obtained by the residual oil hydrodemetallization method and the hydrogenation effluent obtained by independently taking a residual oil raw material as a liquid-phase feed and using no hydrogenation protective agent in a hydrodemetallization reaction zone respectively obtain hydrogenation effluents only under the conditions of different feeding and catalyst grading modes, wherein the independently taking the residual oil raw material as the liquid-phase feed and using no hydrogenation protective agent in the hydrodemetallization reaction zone means that compared with the residual oil hydrodemetallization method, ethylene tar is replaced by the same residual oil raw material with equal mass, and the hydrogenation protective agent in the hydrodemetallization zone is replaced by the hydrogenation demetallization catalyst adjacent to the upstream with equal volume, and the others are the same as the residual oil hydrodemetallization method.

The invention also provides a residual oil hydrotreating method, wherein the hydrogenation effluent is subjected to hydrogenation reaction in a hydrodesulfurization reaction zone and a hydrodenitrogenation and/or hydroconversion reaction zone to obtain a hydrogenation product.

And the hydrogenation product enters a separation system to separate gasoline, diesel oil and hydrogenation heavy oil, wherein the hydrogenation heavy oil is preferably used as a feed of a catalytic cracking device.

The hydrodesulfurization reaction zone mainly performs hydrodesulfurization reaction, and is generally provided with at least one hydrodesulfurization catalyst bed, the hydrodenitrogenation and/or hydroconversion reaction zone mainly performs hydrodenitrogenation and hydroconversion reaction, and is generally provided with at least one hydrodenitrogenation and/or hydroconversion catalyst bed.

In the residue hydrotreating process of the present invention, the hydrodesulfurization catalyst, hydrodenitrogenation catalyst, and/or conversion catalyst may be selected from commercial catalysts conventional in the art or prepared by conventional methods of the prior art. The catalyst comprises a carrier and an active metal component, wherein the carrier can be an alumina-based carrier, and at least one of boron, silicon, zirconium, phosphorus, fluorine, titanium and the like can be added, the active metal component is generally selected from one or more of group VIB and/or group VIII metals, the group VIII metal is preferably Ni and/or Co, and the group VIB metal is preferably Mo and/or W. The catalyst of the present invention may be in the form of an extrudate or a sphere. For example, FZC-series commercial catalysts developed by the institute of petrochemical and comforting petrochemical industries of china, such as hydrodesulfurization catalyst FZC-33B, hydrodenitrogenation catalyst FZC-41C, and the like, can be used. In the residual oil hydrotreating method of the present invention, the filling type and the amount of each catalyst can be adjusted by those skilled in the art according to actual needs.

Compared with the prior art, the invention has the following beneficial technical effects:

(1) the method is discovered by the inventor surprisingly, ethylene tar is used as a material viscosity adjusting aid and added into the residual oil raw material, so that the demetallization performance of a reaction system is not reduced but promoted under the condition of the hydrodemetallization reaction, indexes such as viscosity, metal removal rate and the like of reaction effluent at the stage are obviously improved, the diffusibility of the reaction system under the condition of the hydrodemetallization reaction can be judged to be more favorable for the demetallization reaction, the system viscosity under the reaction condition is effectively reduced by the synergistic effect of the components, the residual oil hydrodemetallization is promoted, and the promotion of the subsequent reactive performances such as desulfurization, carbon residue removal and the like is also favorable.

(2) In the conventional hydrodemetallization reaction zone, a hydrodemetallization catalyst is generally filled, and the filling principle of the hydrodemetallization catalyst is generally along the direction of liquid-phase material flow, the activity of the hydrodemetallization catalyst is gradually increased, the particle size of the hydrodemetallization catalyst is gradually reduced, the pore size of the hydrodemetallization catalyst is gradually reduced, and the like.

(3) The method can be carried out on a conventional residual oil hydrotreater, and is easy to industrialize.

Drawings

FIG. 1 is a graph comparing the viscosity of the hydrogenated effluent obtained in example 1 and comparative example 1 at different run times;

FIG. 2 is a graph comparing the removal rates of metallic Ni and V of the hydrogenation effluents obtained in example 1 and comparative example 1 at different running times;

FIG. 3 is a graph comparing the sulfur removal rates of the hydrogenation effluents obtained in example 1 and comparative example 1 at different run times.

Detailed Description

The present invention is further illustrated by the following examples, but the scope of the present invention is not limited by the examples. In the present invention, wt% is a mass fraction.

Comparative example 1

This comparative example employed a fixed bed reactor R1 in which a hydrogenation protection reaction zone and a hydrodemetallization reaction zone were disposed, and the catalysts charged in each reaction zone are shown in Table 2.

Preheating and mixing the residual oil raw material A, then feeding the mixture and hydrogen into a reactor in an upper feeding mode, sequentially contacting with catalysts graded in the table 2 under the condition of hydrodemetallization, and carrying out hydrogenation reaction to obtain a hydrogenation effluent, wherein the properties of the hydrogenation effluent are shown in the table 3. The viscosity of the hydrogenation effluent, the removal of metallic Ni and V and the removal of sulfur at different run times are shown in figures 1-3, respectively.

Wherein, the properties of the residual oil raw material A and the ethylene tar A are shown in a table 1, the types and the grades of the catalysts are shown in a table 2, wherein the hydrogenation protective agent is FZC-1 series, and the hydrogenation demetalization catalyst is FZC-2 series. The process conditions are shown in Table 3, and the fixed bed hydrogenation results are shown in Table 4.

Example 1

The process of this example is substantially the same as comparative example 1, except that: ethylene tar a was used in place of part of the residuum feed a (see table 3) and part of the hydrodemetallization catalyst was replaced with part of the hydro protectant (see table 2). Wherein, the process conditions are shown in Table 3, and the fixed bed hydrogenation results are shown in Table 4. The viscosity of the hydrogenation effluent, the removal of metallic Ni and V and the removal of sulfur at different run times are shown in figures 1-3, respectively.

Example 2

This embodiment is basically the same as embodiment 1, except that: the feed of this example was made up of residuum feedstock B, ethylene tar B, heavy cycle oil and different catalyst grading schemes, the process conditions are shown in Table 3, the catalyst grading is shown in Table 2, and the fixed bed hydrogenation results are shown in Table 4.

Example 3

This example is essentially the same as example 1, except that the feed of this example was made of resid feed A and ethylene tar B, and different catalyst grading patterns, the process conditions are shown in Table 3, the catalyst grading is shown in Table 2, and the fixed bed hydrogenation results are shown in Table 4.

Example 4

This embodiment is basically the same as embodiment 1, except that: the amount of ethylene tar A and the process conditions were adjusted, the process conditions are shown in Table 3, and the fixed bed hydrogenation results are shown in Table 4.

Example 5

A reactor R2 is added to a reactor R1 in example 1, and a reactor R2 is provided with a hydrodesulfurization reaction zone and a hydrodenitrogenation reaction zone, wherein the catalyst filled in each reaction zone is shown in Table 5.

Preheating and mixing a residual oil raw material A and ethylene tar A, then sequentially entering reactors R1 and R2 which are arranged in series in an upper feeding mode together with hydrogen, sequentially contacting with catalysts which are graded in a table 5 under a hydrotreating condition, carrying out hydrogenation reaction to obtain a hydrogenation product, discharging the obtained product from the bottom of the reactor R2, entering a separation system, separating a small amount of gasoline and diesel oil fractions, and feeding other fractions (fractions above 350 ℃), namely hydrogenation heavy oil, into a catalytic cracking device.

Wherein, the properties of the residual oil raw material A and the ethylene tar A are shown in a table 1, the types and the grades of the catalysts are shown in a table 5, wherein the hydrogenation protective agent is FZC-1 series, the hydrogenation demetallization catalyst is FZC-2 series, the hydrogenation desulfurization catalyst is FZC-3 series, and the hydrogenation denitrification catalyst is FZC-4 series. The process conditions for the two fixed bed reactors are shown in Table 6 and the fixed bed hydrogenation results are shown in Table 7.

Comparative example 2

The process of this comparative example is essentially the same as example 1, except that: a residual oil feedstock a containing polyaromatic oil (catalytic cracking cycle oil, properties see table 1) was used instead of a residual oil feedstock a containing ethylene tar a. Wherein, the process conditions are shown in Table 3, and the fixed bed hydrogenation results are shown in Table 4.

Comparative example 3

The process of this comparative example is substantially the same as comparative example 1, except that: a residual oil feedstock a containing a polyaromatic oil (catalytic cracked recycle oil, properties see table 1) was used instead of residual oil feedstock a. Wherein, the process conditions are shown in Table 3, and the fixed bed hydrogenation results are shown in Table 4.

Comparative example 4

The process of this comparative example is essentially the same as example 1, except that: the residual oil raw material A containing the catalytic cracking heavy cycle oil (the properties are shown in the table 1) is adopted to replace the residual oil raw material A containing the ethylene tar A. Wherein, the process conditions are shown in Table 3, and the fixed bed hydrogenation results are shown in Table 4.

Comparative example 5

The process of this comparative example is substantially the same as comparative example 1, except that: the residue feedstock a containing a catalytically cracked heavy cycle oil (properties see table 1) was used instead of residue feedstock a. Wherein, the process conditions are shown in Table 3, and the fixed bed hydrogenation results are shown in Table 4.

Comparative example 6

The process of this comparative example is essentially the same as example 1, except that: ethylene tar A is used as a raw material to replace residual oil raw material A containing ethylene tar A. Wherein, the process conditions are shown in Table 3, and the fixed bed hydrogenation results are shown in Table 4.

Comparative example 7

The process of this comparative example is essentially the same as example 5, except that: one reactor R2 was added to the one reactor R1 of comparative example 1, and the residuum feed a was used as feed. Wherein, the process conditions are shown in Table 6, and the hydrogenation results are shown in Table 7.

Comparative example 8

The process of this comparative example is essentially the same as example 5, except that: comparative example 3a reactor R2 was added to the reactor R1 and a residual feedstock a containing a polyaromatic oil (catalytic cracked cycle oil, properties see table 1) was used as feed. Wherein, the process conditions are shown in Table 6, and the hydrogenation results are shown in Table 7.

TABLE 1 analysis of properties of residua feedstock, ethylene tar and light oil

Item	Residual oil feedstock A	Residual oil feedstock B	Ethylene tar A	Ethylene tar B	Polyaromatic hydrocarbon oil	Heavy cycle oil	Analytical method
								Sulfur content, μ g/g	30600	28400	494	351	1900	15600	SH/T0689-2000
Nitrogen content,. mu.g/g	3002	4831	27	17	1400	2100	SH/T0704-2001
								Carbon residue in wt%	13.65	11.21	20.16	12.41	0.23	0.65	GB/T 17144-1997
Heavy metal content
								Ni，μg/g	22.32	19.36	0.16	0.261	-	3.45	ASTM D5708-2005
V，μg/g	68.45	65.42	2.80	0.008	-	5.26	ASTM D5708-2005
								Freezing point, deg.C	32	25	34	32	-	-	GB/T 510-1983
Viscosity, 100 ℃ in mm/s	93.66	92.17	317.8	285.0	-	8.90	GB/T 11137
								Density (20 ℃ C.), g/cm³	0.9875	0.9828	1.1197	1.043	0.957	1.056	GB/T 13377-1992
Simulation of distillation,% of							ASTM D7169-2005
								IBP/10，℃	228/455	243/472	165/238	156/224	186/228	222/363
30/50，℃	545/586	547/605	358.6/478.4	343/462	256/293	387/402
								70/90，℃	621/679	643/695	558.2/676	541/658	318/359	419/445
95.3，℃	694	714	750	730	375	470

TABLE 2 catalyst grading schemes (by volume fraction)

	R1-hydrogenation protection reaction zone	R1-hydrodemetallization reaction zone
			Comparative example 1	FZC-100B：FZC-12B ：FZC-103D：FZC-13B =7:8:8:23	FZC-28A: FZC-204A=45：86
Example 1	FZC-100B：FZC-12B ：FZC-103D：FZC-13B =7:8:8:23	FZC-28A: FZC-13B：FZC-204A=40：5：86
			Example 2	FZC-100B：FZC-12B ：FZC-103D：FZC-13B =7:8:8:23	FZC-28A: FZC-13B：FZC-204A：FZC-13B：FZC-204A =45：3：50：4：29
Example 3	FZC-100B：FZC-12B ：FZC-103D：FZC-13B =7:8:8:23	FZC-28A:FZC-13B: FZC-28A:FZC-13B:FZC-204A =35:4:30:4: 58
			Example 4	FZC-100B：FZC-12B ：FZC-103D：FZC-13B =7:8:8:23	FZC-28A: FZC-13B：FZC-204A=40：5：86

TABLE 3 Process conditions for the examples

	Example 1	Example 2	Example 3	Example 4
					Raw materials	Residual oil raw material A + ethylene tar A	Residual oil raw material B + ethylene tar B + heavy cycle oil	Residual oil raw material A + ethylene tar B	Residual oil raw material A + ethylene tar A
Weight ratio of ethylene tar to residual oil feedstock	1：10	1：10	1.5：1.0	0.6：10
					Weight ratio of heavy cycle oil to residual oil feedstock	-	0.5：10	-	-
Reactor (R1)
					Partial pressure of hydrogen, MPa	15.6	16.8	17.1	16.8
Reaction temperature of	385	380	383	387
					Liquid hourly volume space velocity, h^-1	0.42	0.40	0.43	0.45
Volume ratio of hydrogen to oil	650	650	750	800

TABLE 3

	Comparative example 1	Comparative example 2	Comparative example 3	Comparative example 4	Comparative example 5	Comparative example 6
							Raw materials	Residual oil feedstock A	Residual oil raw material A + polyaromatic hydrocarbon oil	Residual oil raw material A + polyaromatic hydrocarbon oil	Residual oil raw material A + heavy cycle oil	Residual oil raw material A + heavy cycle oil	Ethylene tar A
Weight ratio of blended oil product to residual oil raw material	-	1 (polyaromatic oil): 10	1 (polyaromatic oil): 10	1：10	1：10	-
							Reactor (R1)
Partial pressure of hydrogen, MPa	15.6	15.6	15.6	15.6	15.6	15.6
							Reaction temperature of	385	385	385	385	385	385
Liquid hourly volume space velocity, h^-1	0.42	0.42	0.42	0.42	0.42	0.42
							Volume ratio of hydrogen to oil	650	650	650	650	650	650

TABLE 4 results of the reactions in the examples

Analysis item	Example 1	Example 2	Example 3	Example 4
					Running time, h	1500	1500	1500	1500
Hydrogenation effluent Properties
					Sulfur content, μ g/g	10887	10595	11056	11459
Nitrogen content,. mu.g/g	2150	3008	2067	2204
					Carbon residue in wt%	8.07	6.71	7.93	8.11
Heavy metal content
					Ni，μg/g	4.72	4.23	4.65	5.85
V，μg/g	14.86	14.15	14.27	15.47
					Freezing point, deg.C	16	16	17	16
Viscosity, 100 ℃ in mm/s	42.50	46.25	50.19	51.27
					Density (20 ℃ C.), g/cm³	0.965	0.963	0.968	0.962

TABLE 4

Analysis item	Comparative example 1	Comparative example 2	Comparative example 3	Comparative example 4	Comparative example 5	Comparative example 6
							Running time, h	1500	1500	1500	1500	1500	500
Hydrogenation effluent Properties
							Sulfur content, μ g/g	12685	12187	11975	11874	11439	276
Nitrogen content,. mu.g/g	2102	2148	2062	2135	2098	14
							Residual carbon content%	8.08	7.98	7.57	8.05	7.87	15.27
Heavy metal content
							Ni，μg/g	6.47	6.17	5.84	6.36	6.05	--
V，μg/g	18.95	18.12	17.32	18.25	17.54	--
							Freezing point, deg.C	18	18	18	18	18	27
Viscosity, 100 ℃ in mm/s	63.53	65.26	58.31	61.62	59.24	198.45
							Density (20 ℃ C.), g/cm³	0.958	0.956	0.955	0.962	0.961	1.050

As can be seen from the comparison of the results of example 1 and comparative example 1 in Table 4, although the carbon residue content of the ethylene tar added in the process of the present invention is higher than that of the residual oil feedstock, the carbon residue removal rate of the process of the present invention is higher than that of comparative example 1, as deduced from the carbon residue content of the hydrogenation effluent.

TABLE 5 catalyst grading schemes (by volume fraction)

	R1-hydrogenation protection reaction zone	R1-hydrodemetallization reaction zone	R2
				Example 5	FZC-100B：FZC-12B ：FZC-103D：FZC-13B =7:8:8:23	FZC-28A：FZC-13B：FZC-204A=40：5：86	FZC-33B：FZC-41A=45:145

TABLE 6 Process conditions for the examples

	Example 5	Comparative example 7	Comparative example 8
				Raw materials	Residual oil raw material A + ethylene tar A	Residual oil feedstock A	Residual oil raw material A + polyaromatic hydrocarbon oil
Weight ratio of ethylene tar to residual oil feedstock	1：10	-	-
				Weight ratio of polyaromatic oil to residual oil feedstock	-	-	1:10
Reactor (R1)
				Partial pressure of hydrogen, MPa	15.6	15.6	15.6
Reaction temperature of	385	385	385
				Liquid hourly volume space velocity, h^-1	0.42	0.42	0.42
Volume ratio of hydrogen to oil	650	650	650
				Reactor (R2)
Partial pressure of hydrogen, MPa	14.9	14.9	14.9
				Reaction temperature of	390	390	390
Liquid hourly volume space velocity, h^-1	0.39	0.39	0.39
				Volume ratio of hydrogen to oil	600	600	600

TABLE 7 hydrogenation results for the examples

Analysis item	Example 5	Comparative example 7	Comparative example 8
				Running time, h	1500	1500	1500
Nature of hydrogenated heavy oil
				Sulfur content, μ g/g	4010	5216	4985
Nitrogen content,. mu.g/g	1612	1627	1546
				Residual carbon content%	5.61	5.58	5.44
Heavy metal content
				Ni，μg/g	3.19	4.21	3.98
V，μg/g	8.71	12.74	12.03
				Freezing point, deg.C	11	13	12
Viscosity, 100 ℃ in mm/s	23.82	34.69	30.21
				Density (20 ℃ C.), g/cm³	0.942	0.935	0.931

To further examine the influence of the method of the present invention on the activity and stability, the catalyst stability test was carried out for example 5 and comparative example 7, the primary hydrogen partial pressure was 15.6MPa, the secondary hydrogen partial pressure was 14.9MPa, and the primary liquid-return hourly space velocity was 0.42 hr^-1Second liquid reaction time volume airspeed of 0.39h^-1An inverse average inverseThe hydrogenation reaction was carried out at a reaction temperature of 385 deg.C, a reaction temperature of 390 deg.C, a reaction temperature of 650 deg.C, and a reaction temperature of 600 deg.C, the reaction results are shown in Table 8.

TABLE 8 residual oil hydrogenation stability test results

Fixed bed reactor		1500h	2000h	2500h	3000h
						Hydrogenated heavy oil S, wt%	Example 5	4010	4143	4307	4518
Hydrogenated heavy oil S, wt%	Comparative example 7	5216	5321	5489	5686
						Hydrogenated heavy oil CCR, wt%	Example 5	5.61	5.94	6.28	6.61
Hydrogenated heavy oil CCR, wt%	Comparative example 7	5.58	5.87	6.29	6.65
						Hydrogenation heavy oil Ni + V, mug/g	Example 5	11.90	12.81	14.27	15.86
Hydrogenation heavy oil Ni + V, mug/g	Comparative example 7	16.95	18.01	19.24	20.53

As can be seen from the comparison of the results of example 5 and comparative example 7 in Table 8, although the carbon residue content of the ethylene tar added in the process of the present invention is higher than that of the residual oil feedstock, the carbon residue removal rate of the process of the present invention is higher than that of comparative example 7 at different operation times, as deduced from the carbon residue content of the hydrogenated heavy oil.

As can be seen from the examination of the long-time operation period in the table 8, the unexpected reaction effect is obtained by adopting the residual oil hydrotreating method in the embodiment 5, and after 3000-hour stable operation, the sulfur content in the hydrogenated heavy oil is 4518 mug/g, the carbon residue is less than 6.7%, and the metal is less than 16 mug/g, so that the property of the generated oil obtained by adopting the existing method in the comparative example 7 for reaction is obviously improved, and the operation period of the device is favorably prolonged.

Claims

1. A residual oil hydrodemetallization method is characterized in that the feed comprises a residual oil raw material, hydrogen and a material viscosity adjusting auxiliary agent, and is characterized in that: the material viscosity adjusting auxiliary agent comprises ethylene tar, and the feeding material is subjected to a hydrotreating reaction in a hydrodemetallization reaction zone to obtain a hydrogenation effluent; the hydrodemetallization reaction zone is filled with at least one hydrodemetallization catalyst and at least one hydrogenation protective agent;

according to the direction of liquid-phase material flow, the hydrogenation demetallization catalyst and the hydrogenation protective agent are alternately filled in the hydrogenation demetallization reaction zone; the dosage of the ethylene tar accounts for 0.1-30% of the mass of the residual oil raw material; the properties of the ethylene tar are as follows: the density at 20 ℃ is 1.000g/cm³The above; the content of the carbon residue is 10-30 wt%, the condensation point is 30-40 ℃, and the viscosity is 200-500 mm/s at 100 ℃; the properties of the resid feedstock are as follows: the density at 20 ℃ is 0.955-0.996 g/cm³The carbon residue content is 9-14 wt%, the content of metal impurities is 10-110 mu g/g calculated by Ni and V, the condensation point is 27-38 ℃, and the viscosity at 100 ℃ is 60-120 mm/s.

2. The method of claim 1, wherein: according to the direction of liquid phase material flow, the most upstream layer and the most downstream layer are provided with hydrodemetallization catalysts.

3. A method according to claim 1 or 2, characterized in that: and when the hydrogenation demetallization catalyst and the hydrogenation protective agent are alternately filled, the hydrogenation protective agent is filled for 1-4 times.

4. A method according to claim 1 or 2, characterized in that: and filling the hydrogenation protective agent for 1-3 times.

5. The method of claim 1, wherein: the total filling volume of the hydrogenation protective agent accounts for 1-12% of the total volume of the catalyst in the hydrogenation demetallization reaction zone.

6. The method of claim 5, wherein: the total filling volume of the hydrogenation protective agent accounts for 2-10% of the total volume of the catalyst in the hydrogenation demetallization reaction zone.

7. The method of claim 1 or 5, wherein: when the hydrodemetallization catalyst and the hydrogenation protective agent are alternately filled, the filling volume of any layer of hydrogenation protective agent accounts for 1% -16% of the filling volume of an upstream adjacent layer of hydrogenation demetallization catalyst.

8. The method of claim 7, wherein: any layer of hydrogenation protective agent accounts for 2-14% of the filling volume of the upstream adjacent layer of hydrogenation demetallization catalyst.

9. The method of claim 1 or 5, wherein: when the hydrodemetallization catalyst and the hydrogenation protective agent are alternately filled, the filling volume of any layer of the hydrodemetallization catalyst accounts for 10-70% of the total volume of the catalyst in the hydrodemetallization reaction zone.

10. The method of claim 1, wherein: the dosage of the ethylene tar accounts for 5-20% of the mass of the residual oil raw material.

11. The method of claim 1, wherein: the dosage of the ethylene tar accounts for 8-20% of the mass of the residual oil raw material.

12. The method of claim 1, wherein: the properties of the ethylene tar are as follows: the density at 20 ℃ is 1.000-1.200 g/cm³。

13. A method according to claim 1 or 12, characterized by: the ethylene tar has a sulfur content of 0.05wt% or less, a nitrogen content of 80 μ g/g or less, and Ni and V contents of 5 μ g/g or less.

14. The method of claim 13, wherein: the content of Ni and V in the ethylene tar is below 3 mu g/g.

15. The method of claim 1, wherein: the operating conditions of the hydrodemetallization reaction zone are as follows: the reaction temperature is 300-410 ℃, the hydrogen partial pressure is 10-20 MPa, and the liquid hourly space velocity is 0.1-2.0 h^-1The volume ratio of hydrogen to oil is 500-2000.

16. The method of claim 15, wherein: the operating conditions of the hydrodemetallization reaction zone are as follows: the reaction temperature is 350-395 ℃, the hydrogen partial pressure is 13-18 MPa, and the liquid hourly space velocity is 0.1-1.5 h^-1。

17. The method of claim 1, wherein: a fixed bed hydrogenation process is adopted, wherein a reactor containing a hydrodemetallization reaction zone adopts an upflow feeding mode or a downflow feeding mode.

18. The method of claim 1, wherein: a hydrogenation protection reaction zone is arranged before the hydrogenation demetallization reaction zone.

19. The method of claim 1, wherein: the viscosity of the hydrogenation effluent obtained by the residual oil hydrodemetallization method is smaller than that of the hydrogenation effluent obtained by independently taking a residual oil raw material as a liquid-phase feed and adopting no hydrogenation protective agent in a hydrodemetallization reaction zone.

20. A method according to claim 1 or 19, characterized by: the removal rate of metal Ni and metal V in the hydrogenation effluent obtained by the residual oil hydrodemetallization method is higher than that of the hydrogenation effluent obtained by independently taking a residual oil raw material as a liquid-phase feed and adopting no hydrogenation protective agent in a hydrodemetallization reaction zone.

21. A method according to claim 1 or 19, characterized by: the removal rate of sulfur in the hydrogenation effluent obtained by the residual oil hydrodemetallization method is higher than that of the hydrogenation effluent obtained by independently taking a residual oil raw material as a liquid-phase feed and adopting no hydrogenation protective agent in a hydrodemetallization reaction zone.

22. The method of claim 20, wherein: the removal rate of sulfur in the hydrogenation effluent obtained by the residual oil hydrodemetallization method is higher than that of the hydrogenation effluent obtained by independently taking a residual oil raw material as a liquid-phase feed and adopting no hydrogenation protective agent in a hydrodemetallization reaction zone.

23. The method of claim 1, wherein: the resid feedstock comprises an atmospheric resid and/or a vacuum resid.

24. The method of claim 23, wherein: the residual oil raw material also comprises an auxiliary raw material, wherein the auxiliary raw material is a light oil product obtained by straight-run, vacuum or secondary processing, and the secondary processing is at least one of coking, catalytic cracking and viscosity reduction.

25. A residual oil hydrotreating method is characterized in that: the hydrogenated effluent of any of claims 1 to 24 is subjected to a hydrogenation reaction in a hydrodesulfurization reaction zone and a hydrodenitrogenation and/or hydroconversion reaction zone to produce a hydrogenated product.